Chapter 11 - Mechanical recycling of packaging waste

Abstract

Thermoplastics are primarily used as packaging materials that—unlike those used in automobile production, the electronics, and construction industries—show life cycles of <1 year and substantial return flows worldwide of about 150 million tonnes per annum. Today, forecasts of considerably increased production of plastics and their contamination of aquatic and soil systems throughout the world have prompted more stringent legal requirements as well as industrial initiatives to manage the resource “plastics” more sustainably. Regarding packaging wastes, there are established process chains that generate preconcentrates of different qualities via mechanically based methods and that consist of a combination of comminution, conditioning, sorting, and compacting steps. During the first enrichment level, the resource plastics, at best, should be highly preconcentrated through collection and technical treatment. The subsequent refining process aims to separate out the remaining foreign materials and impurities and then make available a suitable material for further processing. Altered target objectives on the individual levels lead to the implementation of various processes that are mostly unique and are geared to upstream waste collection systems and/or technological processes. The wide variety of materials poses a huge challenge for generating defined recycling materials. Thus, the highest recycling qualities (food grade) place high demands on waste collection and technology.